<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            width: 300px;
            height: 250px
        }
        .div1 {
            background-color: brown;
            float: left;
            position: relative;
            z-index: 99;
        }
        .div2 {
            background-color: black;
            position: fixed;
            z-index: 0;
            top: 0px;
            left: 50px;
        }
    </style>
</head>
<body>
    <div class="div1">
        <div class="div2"></div>
    </div>
    
</body>
</html>